This alert reminds people to start from the top of the structure when hand tools such as jackhammers, sledge hammers, and picks are used to demolish a structure.
Background
In a recent incident, a brick wall collapsed on a worker causing his death. The worker had knocked out a bottom section of the wall with a sledgehammer. The entire wall was to be removed to enlarge a storage area within an established building in the Sydney CBD.
Contributing factors
Preliminary findings indicate that the wall was weakened to the point of collapse when the bottom section of the wall was knocked out.
Action required
Those in control of work should ensure the following:
- Workers are competent and have received training and instructions on safe demolition methods before starting. Competence should be verified through assessment and regular reinforcement.
- The work is supervised by competent person(s).
- The demolition procedure is prepared and is appropriate for the demolition method to be used. The procedure should be specific for the site and sequential.
- When removing entire wall sections using manual demolition methods that incorporate hand tools, such as jackhammers, sledge hammers, and picks, avoid weakening the wall by:
- never taking down multiple rows of brick at once or starting at the bottom of the wall
- the top course of bricks using a hammer and chisel
- an entire row before starting the next.
- When removing a portion of a wall where masonry will remain above the opening (eg to install a door or window), the upper area of masonry should be supported prior to commencing demolition and the demolition should commence at the top of the intended opening.
- Exclusion zones are established to keep unauthorised people outside of potential collapse zones and areas affected by rebounding material.
- A safe work method statement is developed for any high risk construction work that is undertaken as part of the demolition work. This must be prepared in consultation with workers undertaking the activity and implemented during the demolition.
- Safety glasses, a dust mask, gloves and long-sleeved clothes are worn as protection from flying objects and dust.
- Hearing protection is worn to protect against excessive noise levels.
- Fall protection is in place where work is done at heights.
- Workers do not work from the top of a wall that is being demolished.
- A wall is not to be permitted to stand unless it is effectively supported against collapse. This includes checking whether the wall to be demolished is providing support for other walls.
Further information
The Work Health and Safety Act 2017 (WHS Act) requires a person conducting a business or undertaking to ensure, so far as is reasonably practicable, that safe systems of work are provided and maintained and that all workers are provided with the necessary information, training, instruction or supervision.
- AS2601: Demolition of Structures
- Identification tool for demolition: hazard profile
- Call SafeWork NSW on 13 10 50 or visit www.safework.nsw.gov.au